1. Field of the Invention
The present invention relates to missile systems. More specifically, the present invention relates to optically guided missile systems.
2. Description of the Related Art
For certain applications, optical systems are preferred for missile guidance. Current optically-guided missiles are often constrained by the need to balance aerodynamic considerations and optical considerations with respect to the missile dome. That is, from an optical perspective, a flat dome is preferred. However, from an aerodynamic perspective, an elongate aerodynamically shaped dome is preferred to reduce drag. Hence, using conventional teachings, an optically-guided missile can not be optimized with respect to either aerodynamic or optical considerations and consequently the designer is forced to accept certain performance compromises to meet design objectives.
Accordingly, there is a need in the art for a missile having a conformal dome. That is, there is a need in the art for a missile having an optical guidance system which allows for the dome to be xe2x80x98conformedxe2x80x99 for aerodynamic considerations.
The need in the art is addressed by the missile of the present invention. The inventive missile includes a dome within which a novel optical arrangement is retained. The optical arrangement includes a first prism mounted for rotation about an optical axis and a second prism mounted for rotation about the optical axis.
In the illustrative embodiment, the first and second prisms are Risley prisms. In addition, the illustrative implementation includes a first motor arrangement for rotating the first prism about the optical axis and a second motor arrangement for rotating the second prism about the optical axis. A controller is provided for activating the first and second motors to steer the beam at an angle +and nod the beam at an angle xcex8.
In a specific implementation, the first prism and/or the second prism have at least one surface contoured to correct for optical aberration. A teaching is provided to contour the surface to correct for astigmatism, coma, trefoil, oblique and/or focus. The contour is effected by laser etching, micro-machining, optical thin-film coating or other such technique known in the art.